I got this reply back in 2015, but I never made a blog post about it. I had written to the Duke of Kent for his 80th Birthday. This was my first reply from the Duke of Kent.
The envelope is the usual from the British Royals at the time. You will notice though that this uses the older postmark with the old EIIR Design and old W7047 PPI number for the Sovereign Grant. The back of the envelope is blank.
Inside is a letter from the Duke's then Private Secretary Nicholas Marden. Marden retired in 2018. The letter features The Duke of Kent's Badge at the top along with the address for his office.
The Telephone and Fax (Facsimile) numbers are for the Public Information Office at Buckingham Palace. (I am not sure they still use the fax number as it is no longer listed on the Royal Website.)
20 October 2015
Dear Miss Daly,
His Royal Highness The Duke of Kent has asked me to thank you for your thoughtful letter sent to him on the occasion of his eightieth birthday.
He sends you his best wishes.
Yours Sincerely,
Nick
Nicolas Marden
Private Secretary to HRH The Duke of Kent
If we take a close look at the badge, you will see some elements that may remind you of other badges. The center has an E for Edward, the Duke's first name. Surrounding that is the Order of Garter Belt, with the orders' motto "Honi Soit Qui Maly Pense," which is Middle French for "Shame on him who thinks evil of it." The top is the Coronet of the child of a son of a sovereign. The Duke of Kent is the son of Prince George, Duke of Kent, who was the son of King George V. This coronet is also used on the York Princess's Monogram. The Cambridges and Sussexes use a different coronet as a child of an heir apparent.